JOPSS - Search Results

The temperature and energy dependence of spin excitations in an optimally P-doped BaFe(As $_{0.7}$ P $_{0.3}$ ) superconductor (T = 30 K) were studied by using inelastic neutron scattering. Experimental results are consistent with calculations from a combined density functional theory and dynamical mean field theory, and suggest that the decreased average pnictogen height in BaFe(As $_{0.7}$ P $_{0.3}$ ) reduces the strength of electron correlations and increases the effective bandwidth of magnetic excitation.

Journal Articles

ITER magnet systems; From qualification to full scale construction

Nakajima, Hideo; Hemmi, Tsutomu; Iguchi, Masahide; Nabara, Yoshihiro; Matsui, Kunihiro; Chida, Yutaka; Kajitani, Hideki; Takano, Katsutoshi; Isono, Takaaki; Koizumi, Norikiyo; et al.

Proceedings of 24th IAEA Fusion Energy Conference (FEC 2012) (CD-ROM), 8 Pages, 2013/03

http://www-naweb.iaea.org/napc/physics/FEC/FEC2012/papers/578_ITR24.pdf

The ITER organization and 6 Domestic Agencies (DA) have been implementing the construction of ITER superconducting magnet systems. Four DAs have already started full scale construction of Toroidal Field (TF) coil conductors. The qualification of the radial plate manufacture has been completed, and JA and EU are ready for full scale construction. JA has qualified full manufacturing processes of the winding pack with a 1/3 prototype and made 2 full scale mock-ups of the basic segments of TF coil structure to optimize and industrialize the manufacturing process. Preparation and qualification of the full scale construction of the TF coil winding is underway by EU. Procurement of the manufacturing equipment is near completion and qualification of manufacturing processes has already started. The constructions of other components of the ITER magnet systems are also going well towards the main goal of the first plasma in 2020.

Journal Articles

Positron annihilation study of 4H-SiC by Ge implantation and subsequent thermal annealing

Yu, R. S.*; Maekawa, Masaki; Kawasuso, Atsuo; Wang, B. Y.*; Wei, L.*

Nuclear Instruments and Methods in Physics Research B, 270, p.47 - 49, 2012/01

https://doi.org/10.1016/j.nimb.2011.10.006

Times Cited Count：7 Percentile：43.52(Instruments & Instrumentation)

Journal Articles

Identified charged hadron production in collisions at = 200 and 62.4 GeV

Adare, A.*; Afanasiev, S.*; Aidala, C.*; Ajitanand, N. N.*; Akiba, Yasuyuki*; Al-Bataineh, H.*; Alexander, J.*; Aoki, Kazuya*; Aphecetche, L.*; Armendariz, R.*; et al.

Physical Review C, 83(6), p.064903_1 - 064903_29, 2011/06

https://doi.org/10.1103/PhysRevC.83.064903

Times Cited Count：184 Percentile：99.44(Physics, Nuclear)

Transverse momentum distributions and yields for $pi^{pm}, K^{pm}, p$ , and in collisions at = 200 and 62.4 GeV at midrapidity are measured by the PHENIX experiment at the RHIC. We present the inverse slope parameter, mean transverse momentum, and yield per unit rapidity at each energy, and compare them to other measurements at different collisions. We also present the scaling properties such as and scaling and discuss the mechanism of the particle production in collisions. The measured spectra are compared to next-to-leading order perturbative QCD calculations.

Journal Articles

Azimuthal correlations of electrons from heavy-flavor decay with hadrons in and Au+Au collisions at $sqrt{s_{NN}}$ = 200 GeV

Adare, A.*; Afanasiev, S.*; Aidala, C.*; Ajitanand, N. N.*; Akiba, Yasuyuki*; Al-Bataineh, H.*; Alexander, J.*; Aoki, Kazuya*; Aphecetche, L.*; Aramaki, Y.*; et al.

Physical Review C, 83(4), p.044912_1 - 044912_16, 2011/04

https://doi.org/10.1103/PhysRevC.83.044912

Times Cited Count：8 Percentile：49.7(Physics, Nuclear)

Measurements of electrons from the decay of open-heavy-flavor mesons have shown that the yields are suppressed in Au+Au collisions compared to expectations from binary-scaled collisions. Here we extend these studies to two particle correlations where one particle is an electron from the decay of a heavy flavor meson and the other is a charged hadron from either the decay of the heavy meson or from jet fragmentation. These measurements provide more detailed information about the interaction between heavy quarks and the quark-gluon matter. We find the away-side-jet shape and yield to be modified in Au+Au collisions compared to collisions.

Journal Articles

Measurement of neutral mesons in + collisions at = 200 GeV and scaling properties of hadron production

Adare, A.*; Afanasiev, S.*; Aidala, C.*; Ajitanand, N. N.*; Akiba, Y.*; Al-Bataineh, H.*; Alexander, J.*; Aoki, K.*; Aphecetche, L.*; Armendariz, R.*; et al.

Physical Review D, 83(5), p.052004_1 - 052004_26, 2011/03

https://doi.org/10.1103/PhysRevD.83.052004

Times Cited Count：175 Percentile：98.48(Astronomy & Astrophysics)

The PHENIX experiment at RHIC has measured the invariant differential cross section for production of , , and mesons in collisions at = 200 GeV. The spectral shapes of all hadron transverse momentum distributions are well described by a Tsallis distribution functional form with only two parameters, and , determining the high and characterizing the low regions for the spectra, respectively. The integrated invariant cross sections calculated from the fitted distributions are found to be consistent with existing measurements and with statistical model predictions.

Journal Articles

Intense high-contrast femtosecond -shell X-ray source from laser-driven Ar clusters

Chen, L. M.*; Liu, F.*; Wang, W. M.*; Kando, Masaki; Mao, J. Y.*; Zhang, L.*; Ma, J.*; Li, Y. T.*; Bulanov, S. V.; Tajima, Toshiki; et al.

Physical Review Letters, 104(21), p.215004_1 - 215004_4, 2010/05

https://doi.org/10.1103/PhysRevLett.104.215004

Times Cited Count：66 Percentile：89.57(Physics, Multidisciplinary)

Journal Articles

Performance of vanadium redox flow battery with a novel amphoteric ion exchange membrane synthesized by two-step grafting method

Qiu, J.*; Zhai, M.*; Chen, J.; Wang, Y.*; Peng, J.*; Xu, L.*; Li, J.*; Wei, G.*

Journal of Membrane Science, 342(1-2), p.215 - 220, 2009/10

https://doi.org/10.1016/j.memsci.2009.06.043

Times Cited Count：77 Percentile：91.1(Engineering, Chemical)

A novel ETFE-based amphoteric ion exchange membrane (AIEM) was prepared through a two-step radiation induced grafting technique. ETFE film was first grafted with styrene (St) (denoted as ETFE--PS), followed with a sulfonation treatment to obtain a cation exchange membrane (ETFE--PSSA). The ETFE--PSSA membrane was subsequently grafted with dimethylaminoethyl methacrylate (DMAEMA) and then protonated, resulting in an AIEM with both anionic and cationic groups. The obtained AIEM exhibited high ion exchange capacity (IEC) and conductivity, as well as significantly reduced permeability of vanadium ions. Vanadium redox flow battery (VRFB) assembled with the AIEM maintained an open circuit voltage (OCV) higher than 1.3V after placed for 300h, and exhibited higher columbic efficiency and energy efficiency than that with Nafion117 membrane.

Journal Articles

Amphoteric ion exchange membrane synthesized by radiation-induced graft copolymerization of styrene and dimethylaminoethyl methacrylate into PVDF film for vanadium redox flow battery applications

Qiu, J.*; Zhang, J.*; Chen, J.; Peng, J.*; Xu, L.*; Zhai, M.*; Li, J.*; Wei, G.*

Journal of Membrane Science, 334(1-2), p.9 - 15, 2009/05

https://doi.org/10.1016/j.memsci.2009.02.009

Times Cited Count：90 Percentile：93.15(Engineering, Chemical)

Poly(vinylidene difluoride) (PVDF) film was grafted with styrene (St) and dimethylaminoethyl methacrylate (DMAEMA) using irradiation techniques. Through subsequent sulfonation and protonation processes, a new kind of amphoteric ion exchange membrane (AIEM) was synthesized. The grafting yield () increased with absorbed dose and leveled off at about 60 kGy. The properties of the AIEM strongly depended on the composition and of the film, i.e. higher content of DMAEMA brought lower permeability of vanadium ions and conductivity. Finally, an AIEM was assembled and tested in the vanadium redox flow battery (VRFB) system. It was found that the VRFB assembled with the AIEM maintained an open circuit voltage (OCV) higher than 1.2V after placed for 68h, which was much longer than that with the Nafion117 membrane. Therefore, this work provides a novel method to develop potential substitute of Nafion membranes to be applied in VRFB system.

Journal Articles

Radiation effects on hydroxypropyl methylcellulose phthalate in aqueous system

Xu, L.*; Yue, Z.*; Wang, M.*; Zhai, M.*; Yoshii, Fumio; Seko, Noriaki; Peng, J.*; Wei, G.*; Li, J.*

Nuclear Instruments and Methods in Physics Research B, 265(1), p.394 - 398, 2007/12

https://doi.org/10.1016/j.nimb.2007.09.012

Times Cited Count：5 Percentile：40.96(Instruments & Instrumentation)

A water insoluble cellulose derivative, hydroxypropyl methylcellulose phthalate (HPMCP) hydrogels, was converted to Na type to form hydrogel in paste-like status by radiation crosslinking. Mechanism for radiation crosslinking of cellulose-derivatives in paste-like status was discussed. Crosslinkers, i.e., methyl -bis-acrylamide (MBA) or ethyleneglycol dimethacrylate (EGDMA) has been used to decrease gelation dose (Dg) of synthesis HPMCP hydrogels and improve its mechanical properties. MBA was found to be more effective for accelerating the crosslinking of HPMCP than EGDMA. Swelling degree of HPMCP hydrogel in many kinds ofsalt solutions followed Hofmeister series, which is ubiquitous in polyelectrolyte hydrogel. Specific reswelling was observed in concentrated KF solution, implying a very strong F $^{-}$ binding ability of benzyl group. The comprehensive results obtained in this study will be utilized on the design of HPMCP-based controlled release system.

Journal Articles

Recent progress on the development and analysis of the ITPA global H-mode confinement database

McDonald, D. C.*; Cordey, J. G.*; Thomsen, K.*; Kardaun, O. J. W. F.*; Snipes, J. A.*; Greenwald, M.*; Sugiyama, L.*; Ryter, F.*; Kus, A.*; Stober, J.*; et al.

Nuclear Fusion, 47(3), p.147 - 174, 2007/03

https://doi.org/10.1088/0029-5515/47/3/001

Times Cited Count：51 Percentile：29.82(Physics, Fluids & Plasmas)

This paper describes the updates to and analysis of the International Tokamak Physics Activity (ITPA) Global H-node Confinement Database version 3 (DB3) over the period 1994-2004. Global data, for the energy confinement time and its controlling parameters, have now been collected from 18 machines of different sizes and shapes: ASDEX, ASDEX Upgrade, C-Mod CoMPASS-D, DIII-D, JET, JFT-2M, JT-60U, MAST, NSTX, PBX-M, PDX, START, T-10, TCV, TdeV, TFTR and TUMAN-3M. A wide range of physics studies has been performed on DB3 with particular progress made in the separation of core and edge behavior, dimensionless parameter analyses and the comparison of the database with one-dimensional transport code. A key aim of the database has always been to provide a basis for estimating the energy confinement properties of next step machines such as ITER, and so the impact of the database and its analysis on such machines is also discussed.

Journal Articles

Experimental study on $_{alpha}$ X-ray emission from intense femtosecond laser-solid interactions

Xu, M. H.*; Chen, L.-M.; Li, Y.-T.*; Yuan, X.-H.*; Liu, Y.-Q.*; Nakajima, Kazuhisa; Tajima, Toshiki; Wang, Z.-H.*; Wei, Z.-Y.*; Zhao, W.*; et al.

Acta Physica Sinica, 56(1), p.353 - 358, 2007/01

https://doi.org/10.7498/aps.56.353

Times Cited Count：5 Percentile：37.28(Physics, Multidisciplinary)

The characteristics of $_{alpha}$ X-ray sources generated by p-polarized femtosecond laser-solid interactions are experimentally studied in the relativistic regime. By use of knife-edge image technique and a single-photon-counting X-ray CCD camera, we obtain the source size, the spectrum and the conversion efficiency of the $_{alpha}$ X-ray sources. The experimental results show that the conversion efficiency of $_{alpha}$ photons reaches an optimum value 7.0810 $^{-6}$ /sr at the laser intensity of 1.610 $^{18}$ W/cm $^{2}$ , which is different from the Reich's simulation results. We find that about 10% of laser energy is converted into the forward hot electrons at the laser intensity of 1.610 $^{18}$ W/cm $^{2}$ .

Journal Articles

Scaling of the energy confinement time with and collisionality approaching ITER conditions

Cordey, J. G.*; Thomsen, K.*; Chudnovskiy, A.*; Kardaun, O. J. W. F.*; Takizuka, Tomonori; Snipes, J. A.*; Greenwald, M.*; Sugiyama, L.*; Ryter, F.*; Kus, A.*; et al.

Nuclear Fusion, 45(9), p.1078 - 1084, 2005/09

https://doi.org/10.1088/0029-5515/45/9/007

Times Cited Count：51 Percentile：82.4(Physics, Fluids & Plasmas)

The condition of the latest version of the ELMy H-mode database has been re-examined. It is shown that there is bias in the ordinary least squares regression for some of the variables. To address these shortcomings three different techniques are employed: (a)principal component regression, (b)an error in variables technique and (c)the selection of a better conditioned dataset with fewer variables. Scalings in terms of the dimensionless physics valiables, as well as the standard set of engineering variables, are derived. The new scalings give a very similar performance for existing scalings for ITER at the standard beta, but a much improvement performance at higher beta.

Journal Articles

O 2 hole-assisted electronic processes in the Pr $_{1-x}$ Sr $_{x}$ MnO $_{3}$ (x=0.0, 0.3) system

Ibrahim, K.*; Qian, H. J.*; Wu, X.*; Abbas, M. I.*; Wang, J. O.*; Hong, C. H.*; Su, R.*; Zhong, J.*; Dong, Y. H.*; Wu, Z. Y.*; et al.

Physical Review B, 70(22), p.224433_1 - 224433_9, 2004/12

https://doi.org/10.1103/PhysRevB.70.224433

Times Cited Count：29 Percentile：75.08(Materials Science, Multidisciplinary)

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